Precipitation refers to a meteorological phenomenon occurring within the atmosphere, and the level of precipitation is very closely related to the everyday lives of human beings.
Recently, due to the influence of global warming, diverse types of pollution, and environmental contamination, and so on, unexpected rainstorm (or heavy rain) or super typhoon, wind gust, and so on, have become active very suddenly, and, therefore, accurate precipitation measurement is very crucial, and, most particularly, there should be no measurement error in measuring precipitation including wind gust.
Generally, in order to measure precipitation, as shown in FIG. 1, a mechanical bucket-type turnover-type precipitation meter is being used.
In the turnover-type precipitation meter, when a predetermined amount of precipitation is collected in one side of a bucket (1) having the structure of a see-saw, due to its weight, the bucket (1) is tilted to the other side and activates a switch (2), so as to generate a contact signal, and the signal is then converted to a precipitation level.
However, such turnover-type precipitation meters are installed outdoors being exposed to wind, and, accordingly, when the wind blows, malfunction occurs frequently, and, additionally, even when there is no rainfall, in such turnover-type precipitation meter, when wind is introduced through its drainage hole, the see-saw shaped bucket (1) is tilted and activates the switch (2), which frequently leads to precipitation measurement errors indicating rainfall even when there is no rainfall.
The weight-type precipitation meter shown in FIG. 2 corresponds to a precipitation meter that can convert precipitation weight within an instrumentation tank (4) placed above a load cell (3) by using the load cell (3), which is configured to measure weight, and the weight-type precipitation meter is disadvantageous in that precision assembly parts are used, thereby causing the structure to become complicated, causing frequent minor malfunction and failure, and causing an increase in the fabrication cost.
Moreover, precipitation measurement error also occurs in the weight-type precipitation meter when a load applied to the load cell is changed due to wind pressure, which is caused by the wind.
Furthermore, in order to measure a precipitation height per unit area, although the precipitation measurement reference standard is required to convert the precipitation height by measuring a volume of the precipitation, instead of measuring the volume, since both of the above-described turnover-type precipitation meter and the weight-type precipitation meter can convert the precipitation height by measuring the weight, there is a problem of failing to compensate for volumetric difference respective to temperature. In other words, when described more specifically, although precipitation is to be measured by measuring its volume, evidently, since the weight of water varies depending upon the temperature of the water, and, more specifically, since the water weighs the most at 3.98° C., and since its weight decreases gradually at a temperature higher than this, and since the level of precipitation is measured by weight despite such difference in weight, which is caused by the difference in temperature, there lies a problem in that the measurement of the level of precipitation cannot be performed accurately.